Python Program to Find the Square Root

In this program, you'll learn to find square root of a number using exponent operator and cmath module.

For positive numbers using exponent**

#Python program to calculate the square root

#Note : change this value for a different results

num = 8

#uncomment to take input from the user 

#num = float(input('Enter a number:'))

num_sqrt = num**0.5

print('The square root of %0.3f is %0.3f'%(num,num_sqrt)) 

Output

The square root of 8.000 is 2.828

In this program, we store the number in num and find the square root using the ** exponent operator. This program works for all positive works for all positive real numbers. But for negative or complex numbers, it can be as folows. 

For real or complex numbers using cmath module

#Find square root of real or complex numbers

#Import the complex math module

import cmath

#change this value for a different results

num = 1+2j

#uncomment to take input from the user

#num = eval (input('Enter a number:'))

num_sqrt = cmath.sqrt (num)

print('The square root of {0} is {1:0.3f}+{2:0.3f}'.format(num,num_sqrt.real,num_sqrt.imag))

Output

The square root of (1+2j) is 1.272+0.786j 

In this program, we use the sqrt() function in the cmath (complex math) module.

Notice that we have used eval() function instead of float() to convert complex numbers as well. Also notice the way in which the output is formatted.